Version July 2025
Serious and sometimes fatal infections and bleeding occur very rarely following spontaneous, surgical, and medical abortions, including following mifepristone use. No causal relationship between the use of mifepristone and misoprostol and these reactions has been established. Before prescribing mifepristone, inform the patient about the risk of these serious events. Ensure that the patient knows whom to call and what to do, including going to an emergency room, if none of the provided contacts are reachable, if they experience sustained fever, severe abdominal pain, prolonged heavy bleeding, or syncope, or if they experience abdominal pain or discomfort or general malaise (including weakness, nausea, vomiting, or diarrhea) more than 24 hours after taking misoprostol.
Patients with serious bacterial infections (eg, Clostridium sordelli) and sepsis can present without fever, bacteremia, or significant findings on pelvic examination following an abortion. Very rarely, deaths have been reported in patients who presented without fever, with or without abdominal pain, but with leukocytosis with a marked left shift, tachycardia, hemoconcentration, and general malaise. A high index of suspicion is needed to rule out serious infection and sepsis.
Prolonged heavy bleeding may be a sign of incomplete abortion or other complications, and prompt medical or surgical intervention may be needed. Advise patients to seek immediate medical attention if they experience prolonged heavy vaginal bleeding.
Because of the risks of serious complications (eg, bacterial infections, bleeding), mifepristone is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the mifepristone REMS program.
Mifepristone is a potent antagonist of progesterone and cortisol via the progesterone and glucocorticoid (GR-II) receptors, respectively. The antiprogestational effects will result in the termination of pregnancy. Pregnancy must be excluded before the initiation of treatment with mifepristone and prevented during treatment and for 1 month after stopping treatment by the use of a nonhormonal, medically acceptable method of contraception unless the patient has had a surgical sterilization, in which case, no additional contraception is needed. Pregnancy must also be excluded if treatment is interrupted for more than 14 days in females of reproductive potential.
Hyperglycemia in patients with Cushing syndrome (Korlym): Initial dose: Oral: 300 mg once daily. Dose may be increased in 300 mg increments at intervals of ≥2 to 4 weeks based on tolerability and symptom control. Maximum dose: 1,200 mg once daily, not to exceed 20 mg/kg/day. If treatment is interrupted, reinitiate at 300 mg daily or a dose lower than the dose that caused the treatment to be stopped if interruption due to adverse reactions.
Pregnancy loss (miscarriage), first or second trimester (off-label use):
Combination therapy (with misoprostol): Note: Combination therapy with mifepristone and misoprostol is generally preferred to misoprostol monotherapy due to better efficacy (Ref). Refer to Misoprostol monograph for misoprostol dosing.
First trimester:
Oral: 200 mg as a single dose, followed by misoprostol (Ref).
Second trimester:
Oral: 200 mg as a single dose, followed by misoprostol (Ref).
Pregnancy termination, medication abortion (off-label use after 70 days gestation):
Combination therapy (with misoprostol): Note: Combination therapy with mifepristone and misoprostol is generally preferred to misoprostol monotherapy due to better efficacy (Ref). Refer to Misoprostol monograph for misoprostol dosing.
First trimester:
Oral: 200 mg as a single dose, followed by misoprostol (Ref).
Second trimester:
Oral: 200 mg as a single dose, followed by misoprostol (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Hyperglycemia in patients with Cushing syndrome: Maximum dose: 600 mg once daily.
Pregnancy termination: There are no dosage adjustments provided in the manufacturer's labeling (has not been studied).
Hyperglycemia in patients with Cushing syndrome:
Mild to moderate impairment: Maximum dose: 600 mg once daily.
Severe impairment: Use is not recommended.
Note: Following single and multiple doses of 600 mg/day in patients with moderate hepatic impairment (Child-Turcotte-Pugh class B), a large variability in exposure to mifepristone and its metabolites was observed.
Pregnancy termination: There are no dosage adjustments provided in the manufacturer's labeling (has not been studied); use with caution due to CYP3A4 metabolism.
Hyperglycemia in patients with Cushing syndrome: Refer to adult dosing.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.
Hyperglycemia in patients with Cushing syndrome:
>10%:
Cardiovascular: Hypertension, peripheral edema
Endocrine & metabolic: Abnormal thyroid function test, hypokalemia
Gastrointestinal: Decreased appetite, diarrhea, nausea, vomiting, xerostomia
Genitourinary: Endometrium disease (hypertrophy), vaginal hemorrhage
Nervous system: Dizziness, fatigue, headache, pain
Neuromuscular & skeletal: Arthralgia, back pain, limb pain, myalgia
Respiratory: Dyspnea, nasopharyngitis, sinusitis
1% to 10%:
Cardiovascular: Edema, pitting edema
Dermatologic: Maculopapular rash, pruritus
Endocrine & metabolic: Adrenocortical insufficiency, hypoglycemia, increased serum triglycerides, increased thirst, increased thyroid stimulating hormone level
Gastrointestinal: Abdominal pain, anorexia, constipation, gastroesophageal reflux disease
Genitourinary: Abnormal uterine bleeding
Nervous system: Anxiety, asthenia, drowsiness, insomnia, malaise, myasthenia
Neuromuscular & skeletal: Musculoskeletal chest pain
Renal: Flank pain
Frequency not defined:
Cardiovascular: Prolonged QT interval on ECG
Endocrine & metabolic: Decreased HDL cholesterol
Genitourinary: Abortion
Termination of intrauterine pregnancy:
>10%:
Gastrointestinal: Diarrhea (18% to 43%), nausea (51% to 75%), vomiting (37% to 48%)
Nervous system: Asthenia (55% to 58%), chills (≤48%), dizziness (39% to 41%), headache (41% to 44%)
Miscellaneous: Fever (≤48%)
1% to 10%: Hematologic & oncologic: Decreased hemoglobin (6%)
<1%: Infection: Sepsis
Frequency not defined:
Gastrointestinal: Abdominal cramps, abdominal pain
Genitourinary: Abnormal vaginal hemorrhage (prolonged heavy bleeding)
Postmarketing (any indication):
Cardiovascular: Hypotension, orthostatic hypotension, syncope, tachycardia (including rapid pulse and palpitations)
Dermatologic: Acute generalized exanthematous pustulosis (Zhang 2020)
Gastrointestinal: Dyspepsia
Genitourinary: Ectopic pregnancy (rupture), leukorrhea, uterine disease (hematometra), uterine rupture
Hematologic & oncologic: Anemia, hemorrhage
Hepatic: Hepatic injury (Funke 2019)
Hypersensitivity: Anaphylaxis, angioedema, hypersensitivity reaction
Infection: Infection (including bacterial infection [eg, Clostridium sordellii], endometritis, endomyometritis, parametritis, pelvic inflammatory disease, pelvic region infection, salpingitis, septic shock, serious infection, toxic shock syndrome) (Fischer 2005; Gendron 2014; Meites 2010; Murray 2005)
Nervous system: Loss of consciousness
Hypersensitivity to mifepristone or any component of the formulation.
Korlym (additional contraindications): Concomitant use of lovastatin, simvastatin, or CYP3A substrates with a narrow therapeutic range (eg, cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinine, sirolimus, tacrolimus); concomitant use of systemic corticosteroids for life-saving purposes (eg, immunosuppression following organ transplant); women with a history of unexplained vaginal bleeding, or endometrial hyperplasia with atypia or endometrial carcinoma; pregnancy.
Mifeprex (additional contraindications): Hypersensitivity to misoprostol or other prostaglandins; chronic adrenal failure; inherited porphyrias; hemorrhagic disorder or concurrent anticoagulant therapy; intrauterine device in place; ectopic pregnancy or undiagnosed adnexal mass; concurrent long-term corticosteroid therapy.
Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Concerns related to adverse effects:
• Adrenal insufficiency: When used for the treatment of hyperglycemia in patients with Cushing syndrome, adrenal insufficiency may occur. Serum cortisol concentrations remain elevated and may increase and cannot be used for monitoring. If signs and symptoms of adrenal insufficiency occur (eg, fatigue, hypoglycemia, hypotension, nausea, weakness), discontinue mifepristone and administer glucocorticoids (high doses may be needed). Following resolution, treatment may be resumed at a lower dose; evaluate patient for precipitating causes (eg, infection, trauma).
• Bacterial infections: When used for the termination of pregnancy, bacterial infections (eg, Clostridium sordellii) have been reported and may have an atypical presentation. In rare cases, these infections may be serious and/or fatal, with septic shock as a potential complication. A causal relationship has not been established. Promptly evaluate any patient with a fever of ≥38°C (100.4°F) for >4 hours, abdominal pain, or pelvic tenderness; however, atypical presentations of serious infection without these symptoms have also occurred. Evaluate patients presenting with nausea, vomiting, diarrhea, or weakness, with or without abdominal pain or fever for serious bacterial infection when symptoms occur >24 hours after taking misoprostol. Patients with Cushing syndrome may be at risk for opportunistic infections such as Pneumocystis jirovecii pneumonia.
• Bleeding: Regardless of indication, endometrial proliferation is promoted by mifepristone, resulting in endometrial thickening, cystic dilation of endometrial glands, and vaginal bleeding. When used for the termination of pregnancy, counsel patients to seek medical attention for excessive bleeding. Bleeding occurs and should be expected (average 9 to 16 days, may be ≥30 days). In some cases, bleeding may be prolonged and heavy and may be a sign of incomplete abortion or other complications, potentially leading to hypovolemic shock; the manufacturer cites soaking through 2 thick sanitary pads per hour for 2 consecutive hours as an example of excessive bleeding. Bleeding may require blood transfusion (rare), curettage, saline infusions, and/or vasoconstrictors. Instruct patients to seek medical attention if prolonged heavy vaginal bleeding occurs. When used for termination of pregnancy, use caution in patients with severe anemia, hypocoagulability or hemostatic disorders. When used for the treatment of hyperglycemia in patients with Cushing syndrome, use caution with hemorrhagic disorders or concomitant anticoagulants when treating patients who may become pregnant.
• Hypokalemia: May occur at any time during therapy when used to control hyperglycemia in patients with Cushing syndrome. Correct hypokalemia prior to initiation of treatment; monitor potassium levels closely with therapy.
• QT prolongation: May prolong the QTc interval (dose related); use caution with other QT-prolonging agents.
Disease-related concerns:
• Cardiovascular disease: Because mifepristone does not reduce serum cortisol concentrations, mineralocorticoid receptors in cardiac tissue may be activated; use caution in patients with Cushing syndrome who also have heart failure or coronary vascular disease.
Concurrent drug therapy issues:
• Corticosteroids: Use of mifepristone for the treatment of hyperglycemia in patients with Cushing syndrome may antagonize the effects of steroids used for other conditions.
Other warnings/precautions:
• Confirmation of pregnancy termination: Confirm pregnancy termination following treatment. The manufacturer recommends surgical evacuation to manage an ongoing pregnancy in the event of a failed medication abortion. Prescribers should determine in advance whether they will provide such care themselves or through other providers. Take preventive measures to prevent Rh immunization prior to surgical abortion.
• Ectopic pregnancy: Mifepristone is not effective in terminating ectopic pregnancies. As health care providers, be alert for signs/symptoms which may be related to undiagnosed ectopic pregnancy in any patient undergoing a medication abortion; ectopic pregnancy may have been missed even if the patient underwent ultrasonography prior to mifepristone administration.
• Experienced physician: When used for the termination of pregnancy, to be administered only under supervision by qualified health care providers who can date pregnancy, diagnose ectopic pregnancies, provide access to surgical abortion (if needed), and can provide access to emergency care. Medication is available only through the mifepristone REMS Program; may only be dispensed to patients by or under supervision of a certified prescriber, or by certified pharmacies on prescriptions issued by certified prescribers.
• Patient education: When used for the termination of pregnancy, instruct patients of the treatment procedure and expected effects. Keep a signed agreement form in the patient's file. Give the patient clear instructions on whom to call and what to do in the event of an emergency following administration of therapy. Consider appropriate location of initiating therapy; expulsion of pregnancy is expected within 2 to 24 hours after taking misoprostol. Instruct patients undergoing treatment with mifepristone to bring their medication guide with them when obtaining treatment from a health care provider that did not prescribe the medication initially to identify that they are undergoing a medication abortion.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, Oral:
Korlym: 300 mg [contains fd&c yellow #6(sunset yellow)alumin lake, quinoline (d&c yellow #10) aluminum lake]
Mifeprex: 200 mg [contains corn starch]
Generic: 200 mg, 300 mg
Yes
Tablets (Korlym Oral)
300 mg (per each): $830.04
Tablets (Mifeprex Oral)
200 mg (per each): $43.00
Tablets (miFEPRIStone Oral)
200 mg (per each): $60.00
300 mg (per each): $788.54
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
Korlym is only available through a restricted access program. For prescriber registration and patient enrollment forms, please refer to https://www.korlym.com/hcp/access-support/support-program-access-reimbursement-korlym-spark/ or call 1-855-4Korlym (1-855-456-7596).
Hyperglycemia in patients with Cushing syndrome: Administer as a single daily dose with a meal. Swallow tablets whole; do not crush, split, or chew.
Pregnancy termination: Remove any intrauterine device before treatment with mifepristone begins. Administer mifepristone orally and misoprostol buccally, sublingually, or vaginally (Ref). Administer day 1 mifepristone as a single oral dose under supervision of a certified prescriber. Provide patient with phone number and name of provider to call in case of questions or emergencies.
Hazardous agent (NIOSH 2024 [table 2]).
Use appropriate precautions for receiving, handling, storage, preparation, dispensing, transporting, administration, and disposal. Follow NIOSH and USP 800 recommendations and institution-specific policies/procedures for appropriate containment strategy (NIOSH 2023; NIOSH 2024; USP-NF 2020).
Note: Facilities may perform risk assessment of some hazardous drugs to determine if appropriate for alternative handling and containment strategies (USP-NF 2020). Refer to institution-specific handling policies/procedures.
An FDA-approved patient medication guide, which is available with the product and as follows, must be dispensed with this medication:
Korlym: https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/202107s007lbl.pdf#page=19
Mifeprex: https://www.accessdata.fda.gov/drugsatfda_docs/label/2023/020687Orig1s026lbl.pdf#page=16
Hyperglycemia (Korlym): To control hyperglycemia occurring secondary to hypercortisolism in adult patients with endogenous Cushing syndrome who have type 2 diabetes mellitus or glucose intolerance and who failed surgery or who are not surgical candidates.
Limitations of use: Should not be used in the treatment of patients with type 2 diabetes unless it is secondary to Cushing syndrome.
Pregnancy termination, medication abortion (Mifeprex): Pregnancy termination (medication abortion) through 70 days gestation, in combination with misoprostol.
Pregnancy loss (miscarriage), first or second trimester; Pregnancy termination (second trimester), medication abortion, combination therapy
Mifeprex may be confused with Mirapex
MiFEPRIStone may be confused with miSOPROStol
The Institute for Safe Medication Practices (ISMP) includes this medication among its list of drugs (contraindicated in pregnancy) which have a heightened risk of causing significant patient harm when used in error (High-Alert Medications in Community/Ambulatory Care Settings).
Substrate of CYP3A4 (Major); Note: Assignment of Major/Minor substrate status based on clinically relevant drug interaction potential; Inhibits CYP2C9 (Moderate), CYP3A4 (Strong), P-glycoprotein;
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
Abemaciclib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Abemaciclib. Management: In patients taking abemaciclib at a dose of 200 mg or 150 mg twice daily, reduce the dose to 100 mg twice daily when combined with strong CYP3A4 inhibitors. In patients taking abemaciclib 100 mg twice daily, decrease the dose to 50 mg twice daily. Risk D: Consider Therapy Modification
Acalabrutinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Acalabrutinib. Risk X: Avoid
Acrivastine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Acrivastine. Risk C: Monitor
Adagrasib: MiFEPRIStone may increase serum concentration of Adagrasib. Adagrasib may increase serum concentration of MiFEPRIStone. Management: Avoid initiation of mifepristone for the treatment of hyperglycemia in Cushing's syndrome until adagrasib has reached steady state. If combined, mifepristone dose adjustments are recommended. See full monograph for details. Risk D: Consider Therapy Modification
Ado-Trastuzumab Emtansine: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Ado-Trastuzumab Emtansine. Specifically, strong CYP3A4 inhibitors may increase concentrations of the cytotoxic DM1 component. Management: Avoid concomitant use of ado-trastuzumab emtansine and strong CYP3A4 inhibitors when possible. Consider alternatives that do not inhibit CYP3A4 or consider administering after CYP3A4 inhibitor discontinuation. Monitor for toxicities if combined. Risk D: Consider Therapy Modification
Afatinib: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Afatinib. Management: If combined, administer the P-gp inhibitor simultaneously with, or after, the dose of afatinib. Monitor closely for signs and symptoms of afatinib toxicity and if the combination is not tolerated, reduce the afatinib dose by 10 mg. Risk D: Consider Therapy Modification
ALfentanil: CYP3A4 Inhibitors (Strong) may increase serum concentration of ALfentanil. Management: If use of alfentanil and strong CYP3A4 inhibitors is necessary, consider dosage reduction of alfentanil until stable drug effects are achieved. Frequently monitor patients for respiratory depression and sedation when these agents are combined. Risk D: Consider Therapy Modification
Alfuzosin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Alfuzosin. Risk X: Avoid
Aliskiren: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Aliskiren. Risk C: Monitor
Alitretinoin (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Alitretinoin (Systemic). Management: Consider reducing the alitretinoin dose to 10 mg when used together with strong CYP3A4 inhibitors. Monitor for increased alitretinoin effects/toxicities if combined with a strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Almotriptan: CYP3A4 Inhibitors (Strong) may increase serum concentration of Almotriptan. Management: Limit initial almotriptan dose to 6.25 mg and maximum dose to 12.5 mg in any 24-period when used with a strong CYP3A4 inhibitor. Avoid concurrent use in patients with impaired hepatic or renal function. Risk D: Consider Therapy Modification
Alosetron: CYP3A4 Inhibitors (Strong) may increase serum concentration of Alosetron. Risk C: Monitor
ALPRAZolam: CYP3A4 Inhibitors (Strong) may increase serum concentration of ALPRAZolam. Risk X: Avoid
Amiodarone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Amiodarone. Management: Consider alternatives to use of amiodarone and strong CYP3A4 inhibitors. If combined, monitor for increased amiodarone concentrations and toxicities. Risk D: Consider Therapy Modification
AmLODIPine: CYP3A4 Inhibitors (Strong) may increase serum concentration of AmLODIPine. Risk C: Monitor
Androgens: Hypertension-Associated Agents may increase hypertensive effects of Androgens. Risk C: Monitor
Androgens: May increase hypoglycemic effects of Agents with Blood Glucose Lowering Effects. Risk C: Monitor
Anticoagulants: MiFEPRIStone may increase adverse/toxic effects of Anticoagulants. Specifically, the risk of bleeding may be increased. Risk X: Avoid
Antidiabetic Agents: May increase hypoglycemic effects of Hypoglycemia-Associated Agents. Risk C: Monitor
Aprepitant: CYP3A4 Inhibitors (Strong) may increase serum concentration of Aprepitant. Risk X: Avoid
ARIPiprazole Lauroxil: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of ARIPiprazole Lauroxil. Management: Decrease aripiprazole lauroxil dose to next lower strength if used with strong CYP3A4 inhibitors for over 14 days. No dose adjustment needed if using the lowest dose (441 mg). Max dose is 441 mg in CYP2D6 PMs or if also taking strong CYP2D6 inhibitors. Risk D: Consider Therapy Modification
ARIPiprazole: CYP3A4 Inhibitors (Strong) may increase serum concentration of ARIPiprazole. Management: Aripiprazole dose reductions are required for indications other than major depressive disorder. Dose reductions vary based on formulation, initial starting dose, CYP2D6 genotype, and use of CYP2D6 inhibitors. See full interaction monograph for details. Risk D: Consider Therapy Modification
Artemether and Lumefantrine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Artemether and Lumefantrine. CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Artemether and Lumefantrine. Specifically, concentrations of dihydroartemisinin (DHA), the active metabolite of artemether may be increased. Risk C: Monitor
Asciminib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Asciminib. Risk C: Monitor
Atogepant: CYP3A4 Inhibitors (Strong) may increase serum concentration of Atogepant. Management: For treatment of episodic migraine, the recommended atogepant dose is 10 mg once daily with a concurrent strong CYP3A4 inhibitor. If used for treatment of chronic migraine, concurrent use of atogepant with strong CYP3A4 inhibitors should be avoided. Risk D: Consider Therapy Modification
Atorvastatin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Atorvastatin. Risk C: Monitor
Avacopan: CYP3A4 Inhibitors (Strong) may increase serum concentration of Avacopan. Management: Decrease the avacopan dose to 30 mg once daily during coadministration with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Avanafil: CYP3A4 Inhibitors (Strong) may increase serum concentration of Avanafil. Risk X: Avoid
Avapritinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Avapritinib. Risk X: Avoid
Avatrombopag: MiFEPRIStone may increase serum concentration of Avatrombopag. Management: For chronic immune thrombocytopenia, reduce initial avatrombopag dose to 20 mg 3 times per week. No dosage reduction needed for patients with chronic liver disease-associated thrombocytopenia using altrombopag prior to a procedure. Risk D: Consider Therapy Modification
Axitinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Axitinib. Management: Avoid concurrent use of axitinib with any strong CYP3A inhibitor whenever possible. If a strong CYP3A inhibitor must be used with axitinib, a 50% axitinib dose reduction is recommended. Risk D: Consider Therapy Modification
Barnidipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Barnidipine. Risk X: Avoid
Beclomethasone (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Beclomethasone (Systemic). Risk C: Monitor
Bedaquiline: CYP3A4 Inhibitors (Strong) may increase serum concentration of Bedaquiline. CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Bedaquiline. Risk C: Monitor
Benidipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Benidipine. Risk C: Monitor
Benperidol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Benperidol. Risk C: Monitor
Benzhydrocodone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Benzhydrocodone. Specifically, the concentration of hydrocodone may be increased. Risk C: Monitor
Beta-Acetyldigoxin: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Beta-Acetyldigoxin. Risk C: Monitor
Betamethasone (Nasal): CYP3A4 Inhibitors (Strong) may increase serum concentration of Betamethasone (Nasal). Risk C: Monitor
Betamethasone (Ophthalmic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Betamethasone (Ophthalmic). Risk C: Monitor
Betamethasone (Topical): CYP3A4 Inhibitors (Strong) may increase serum concentration of Betamethasone (Topical). Risk C: Monitor
Bilastine: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Bilastine. Risk X: Avoid
Blonanserin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Blonanserin. Risk X: Avoid
Bortezomib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Bortezomib. Risk C: Monitor
Bosentan: MiFEPRIStone may increase serum concentration of Bosentan. Risk X: Avoid
Bosutinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Bosutinib. Risk X: Avoid
Brentuximab Vedotin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Brentuximab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be increased. Risk C: Monitor
Brexpiprazole: CYP3A4 Inhibitors (Strong) may increase serum concentration of Brexpiprazole. Management: Reduce brexpiprazole dose 50% with strong CYP3A4 inhibitors; reduce to 25% of usual if used with both a strong CYP3A4 inhibitor and a CYP2D6 inhibitor in patients not being treated for MDD, or strong CYP3A4 inhibitor used in a CYP2D6 poor metabolizer. Risk D: Consider Therapy Modification
Brigatinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Brigatinib. Management: Avoid concurrent use of brigatinib with strong CYP3A4 inhibitors when possible. If combination cannot be avoided, reduce the brigatinib dose by approximately 50%, rounding to the nearest tablet strength (ie, from 180 mg to 90 mg, or from 90 mg to 60 mg). Risk D: Consider Therapy Modification
Bromocriptine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Bromocriptine. Management: Consider alternatives to the use of bromocriptine with strong CYP3A4 inhibitors. If combined, monitor closely for increased bromocriptine toxicities and consider bromocriptine dose reductions. Risk D: Consider Therapy Modification
Bromperidol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Bromperidol. Risk C: Monitor
Brotizolam: CYP3A4 Inhibitors (Strong) may increase serum concentration of Brotizolam. Risk C: Monitor
Budesonide (Nasal): CYP3A4 Inhibitors (Strong) may increase serum concentration of Budesonide (Nasal). Risk C: Monitor
Budesonide (Oral Inhalation): CYP3A4 Inhibitors (Strong) may increase serum concentration of Budesonide (Oral Inhalation). Management: Consider alternatives to this combination when possible. If combined, monitor for increased corticosteroid adverse effects during coadministration of inhaled budesonide and strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Budesonide (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Budesonide (Systemic). Management: Avoid the concomitant use of CYP3A4 inhibitors and oral budesonide. If patients receive both budesonide and a strong CYP3A4 inhibitor, they should be closely monitored for signs and symptoms of corticosteroid excess. Risk D: Consider Therapy Modification
Budesonide (Topical): CYP3A4 Inhibitors (Strong) may increase serum concentration of Budesonide (Topical). Risk X: Avoid
Buprenorphine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Buprenorphine. Risk C: Monitor
BusPIRone: CYP3A4 Inhibitors (Strong) may increase serum concentration of BusPIRone. Management: Limit the buspirone dose to 2.5 mg daily and monitor patients for increased buspirone effects/toxicities if combined with strong CYP3A4 inhibitors. Dose adjustments of buspirone or a strong CYP3A4 inhibitor should be based on clinical assessment. Risk D: Consider Therapy Modification
Butorphanol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Butorphanol. Risk C: Monitor
Cabazitaxel: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cabazitaxel. Management: Concurrent use of cabazitaxel with strong inhibitors of CYP3A4 should be avoided when possible. If such a combination must be used, consider a 25% reduction in the cabazitaxel dose. Risk D: Consider Therapy Modification
Cabozantinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cabozantinib. Management: Avoid use of a strong CYP3A4 inhibitor with cabozantinib if possible. If combined, decrease cabozantinib capsules (Cometriq) by 40 mg from previous dose or decrease cabozantinib tablets (Cabometyx) by 20 mg from previous dose. Risk D: Consider Therapy Modification
Calcifediol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Calcifediol. Risk C: Monitor
Calcitriol (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Calcitriol (Systemic). Risk C: Monitor
Cannabidiol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cannabidiol. Risk C: Monitor
Cannabis: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Cannabis. More specifically, tetrahydrocannabinol serum concentrations may be increased. Risk C: Monitor
Cannabis: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cannabis. More specifically, tetrahydrocannabinol and cannabidiol serum concentrations may be increased. Risk C: Monitor
Capivasertib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Capivasertib. Management: Avoid concomitant use of capivasertib with strong CYP3A4 inhibitors when possible. If combined, reduce the capivasertib dose to 320 mg twice daily for 4 days, followed by 3 days off. Monitor patients closely for adverse reactions. Risk D: Consider Therapy Modification
Capmatinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Capmatinib. Risk C: Monitor
Cariprazine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cariprazine. CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Cariprazine. Specifically, concentrations of didesmethylcariprazine (DDCAR), the primary active metabolite of cariprazine, may increase. Management: Cariprazine dose adjustments are recommended and depend upon whether a patient is initiating a strong CYP3A4 inhibitor or cariprazine, as well as cariprazine indication. See full mono for details. Some non-US labels contraindicate this combination. Risk D: Consider Therapy Modification
Carvedilol: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Carvedilol. Specifically, concentrations of the S-carvedilol enantiomer may be increased. Risk C: Monitor
Celecoxib: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Celecoxib. Risk C: Monitor
Celiprolol: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Celiprolol. Risk C: Monitor
Ceritinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ceritinib. Management: Avoid this combination whenever possible. If combined, the ceritinib dose should be reduced by approximately one-third (to the nearest 150 mg). Resume the prior ceritinib dose after cessation of the strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
ChlordiazePOXIDE: CYP3A4 Inhibitors (Strong) may increase serum concentration of ChlordiazePOXIDE. Risk C: Monitor
Ciclesonide (Oral Inhalation): CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Ciclesonide (Oral Inhalation). Risk C: Monitor
Cilnidipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cilnidipine. Risk C: Monitor
Cilostazol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cilostazol. Management: Decrease the dose of cilostazol to 50 mg twice daily when combined with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Cinacalcet: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cinacalcet. Risk C: Monitor
Cisapride: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cisapride. Risk X: Avoid
Clindamycin (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Clindamycin (Systemic). Risk C: Monitor
Clofazimine: May increase serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Risk C: Monitor
ClonazePAM: CYP3A4 Inhibitors (Strong) may increase serum concentration of ClonazePAM. Risk C: Monitor
CloZAPine: CYP3A4 Inhibitors (Strong) may increase serum concentration of CloZAPine. Risk C: Monitor
Cobimetinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cobimetinib. Risk X: Avoid
Codeine: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Codeine. Risk C: Monitor
Colchicine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Colchicine. Management: This combination is often contraindicated, but combined use may be permitted with dose adjustment and monitoring. Recommendations vary based on brand, indication, use of P-gp inhibitors, and hepatic/renal function. See interaction monograph for details. Risk D: Consider Therapy Modification
Conivaptan: CYP3A4 Inhibitors (Strong) may increase serum concentration of Conivaptan. Risk X: Avoid
Copanlisib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Copanlisib. Management: If concomitant use of copanlisib and strong CYP3A4 inhibitors cannot be avoided, reduce the copanlisib dose to 45 mg. Monitor patients for increased copanlisib effects/toxicities. Risk D: Consider Therapy Modification
Corticosteroids (Systemic): MiFEPRIStone may decrease therapeutic effects of Corticosteroids (Systemic). MiFEPRIStone may increase serum concentration of Corticosteroids (Systemic). Management: Avoid mifepristone in patients who require long-term corticosteroid treatment of serious illnesses or conditions (eg, for immunosuppression following transplantation). Corticosteroid effects may be reduced by mifepristone treatment. Risk X: Avoid
Crizotinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Crizotinib. Management: Avoid concomitant use of crizotinib and strong CYP3A4 inhibitors whenever possible. If combined use cannot be avoided, crizotinib dose reductions are required, which vary according to indication. See full interaction monograph for details. Risk D: Consider Therapy Modification
CycloSPORINE (Systemic): MiFEPRIStone may increase serum concentration of CycloSPORINE (Systemic). Risk X: Avoid
CYP2B6 Substrates (High risk with Inhibitors): MiFEPRIStone may increase serum concentration of CYP2B6 Substrates (High risk with Inhibitors). Risk C: Monitor
CYP3A4 Inducers (Moderate): May decrease serum concentration of MiFEPRIStone. Management: Avoid combined use in patients treated for Cushing's disease. When used for pregnancy termination, mifepristone efficacy may be reduced and an alternative pregnancy termination procedure may be warranted. Ensure a follow-up assessment after combined use. Risk D: Consider Therapy Modification
CYP3A4 Inducers (Strong): May decrease serum concentration of MiFEPRIStone. Management: Avoid combined use in patients treated for Cushing's disease. When used for pregnancy termination, mifepristone efficacy may be reduced and an alternative pregnancy termination procedure may be warranted. Ensure a follow-up assessment after combined use. Risk D: Consider Therapy Modification
CYP3A4 Inhibitors (Moderate): May increase serum concentration of MiFEPRIStone. Risk C: Monitor
CYP3A4 Inhibitors (Strong): May increase serum concentration of MiFEPRIStone. Management: For treatment of hyperglycemia in Cushing's syndrome, start mifepristone at 300 mg/day, may titrate to a maximum of 900 mg/day. If starting a strong CYP3A4 inhibitor and taking > 300 mg/day mifepristone, decrease the mifepristone dose by 300 mg/day. Risk D: Consider Therapy Modification
Cyproterone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Cyproterone. Risk C: Monitor
Dabrafenib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Dabrafenib. Management: Consider alternatives to any strong CYP3A4 inhibitor for patients being treated with dabrafenib. If such a combination cannot be avoided, monitor closely for evidence of dabrafenib-related adverse effects. Risk D: Consider Therapy Modification
Daclatasvir: CYP3A4 Inhibitors (Strong) may increase serum concentration of Daclatasvir. Management: Decrease the daclatasvir dose to 30 mg once daily if combined with a strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Dapoxetine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Dapoxetine. Risk X: Avoid
Daridorexant: CYP3A4 Inhibitors (Strong) may increase serum concentration of Daridorexant. Risk X: Avoid
Darifenacin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Darifenacin. Management: Limit the darifenacin dose to no more than 7.5 mg daily if combined with strong CYP3A4 inhibitors. Monitor patients for increased darifenacin toxicities (eg, dry mouth, constipation, headache, CNS effects) when these agents are combined. Risk D: Consider Therapy Modification
Darolutamide: Inhibitors of CYP3A4 (Strong) and P-glycoprotein may increase serum concentration of Darolutamide. Risk C: Monitor
Dasatinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Dasatinib. Management: This combination should be avoided if possible. If combined, decrease dasatinib dose from 140 mg to 40 mg, 100 mg to 20 mg, or 70 mg to 20 mg. For patients taking 60 mg or 40 mg daily, stop dasatinib until the CYP3A4 inhibitor is discontinued. Risk D: Consider Therapy Modification
Delamanid: CYP3A4 Inhibitors (Strong) may increase serum concentration of Delamanid. Management: Increase ECG monitoring frequency if delamanid is combined with strong CYP3A4 inhibitors due to the risk for QTc interval prolongation. Continue frequent ECG assessments throughout full delamanid treatment period. Risk D: Consider Therapy Modification
Deuruxolitinib: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Deuruxolitinib. Risk X: Avoid
DexAMETHasone (Ophthalmic): CYP3A4 Inhibitors (Strong) may increase serum concentration of DexAMETHasone (Ophthalmic). Risk C: Monitor
Dexketoprofen: May decrease therapeutic effects of MiFEPRIStone. Risk C: Monitor
DiazePAM: CYP3A4 Inhibitors (Strong) may increase serum concentration of DiazePAM. Risk C: Monitor
Diazoxide Choline: CYP3A4 Inhibitors (Strong) may increase serum concentration of Diazoxide Choline. Risk C: Monitor
Diclofenac (Systemic): CYP2C9 Inhibitors (Moderate) may increase serum concentration of Diclofenac (Systemic). Risk C: Monitor
Dienogest: CYP3A4 Inhibitors (Strong) may increase serum concentration of Dienogest. Risk C: Monitor
Digitoxin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Digitoxin. Risk C: Monitor
Digitoxin: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Digitoxin. Risk C: Monitor
Digoxin: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Digoxin. Management: Measure digoxin serum concentrations before initiating treatment with these P-glycoprotein (P-gp) inhibitors. Reduce digoxin concentrations by either reducing the digoxin dose by 15% to 30% or by modifying the dosing frequency. Risk D: Consider Therapy Modification
DilTIAZem: CYP3A4 Inhibitors (Strong) may increase serum concentration of DilTIAZem. Risk C: Monitor
Disopyramide: CYP3A4 Inhibitors (Strong) may increase serum concentration of Disopyramide. Risk C: Monitor
DOCEtaxel: CYP3A4 Inhibitors (Strong) may increase serum concentration of DOCEtaxel. Management: Avoid the concomitant use of docetaxel and strong CYP3A4 inhibitors when possible. If combined use is unavoidable, consider a 50% docetaxel dose reduction and monitor for increased docetaxel toxicities. Risk D: Consider Therapy Modification
Dofetilide: CYP3A4 Inhibitors (Strong) may increase serum concentration of Dofetilide. Risk C: Monitor
Domperidone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Domperidone. Risk X: Avoid
Doxazosin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Doxazosin. Risk C: Monitor
Doxercalciferol: CYP3A4 Inhibitors (Strong) may decrease active metabolite exposure of Doxercalciferol. Risk C: Monitor
DOXOrubicin (Conventional): P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of DOXOrubicin (Conventional). Risk X: Avoid
DOXOrubicin (Liposomal): P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of DOXOrubicin (Liposomal). Risk C: Monitor
DroNABinol: CYP3A4 Inhibitors (Strong) may increase serum concentration of DroNABinol. Risk C: Monitor
Dronedarone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Dronedarone. Risk X: Avoid
Dutasteride: CYP3A4 Inhibitors (Strong) may increase serum concentration of Dutasteride. Risk C: Monitor
Duvelisib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Duvelisib. Management: Reduce the dose of duvelisib to 15 mg twice a day when used together with a strong CYP3A4 inhibitor. Monitor closely for evidence of altered response to treatment. Risk D: Consider Therapy Modification
Dydrogesterone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Dydrogesterone. Risk C: Monitor
Ebastine: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Ebastine. CYP3A4 Inhibitors (Strong) may increase serum concentration of Ebastine. Risk C: Monitor
Efonidipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Efonidipine. Risk C: Monitor
Elacestrant: CYP3A4 Inhibitors (Strong) may increase serum concentration of Elacestrant. Risk X: Avoid
Elagolix, Estradiol, and Norethindrone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Elagolix, Estradiol, and Norethindrone. Elagolix, Estradiol, and Norethindrone may decrease serum concentration of CYP3A4 Inhibitors (Strong). Specifically, concentrations of strong CYP3A4 inhibitors that are also CYP3A4 substrates may be decreased. Risk X: Avoid
Elagolix: CYP3A4 Inhibitors (Strong) may increase serum concentration of Elagolix. Management: Use of the elagolix 200 mg twice daily dose with a strong CYP3A4 inhibitor for longer than 1 month is not recommended. Limit combined use of the elagolix 150 mg once daily dose with a strong CYP3A4 inhibitor to a maximum of 6 months. Risk D: Consider Therapy Modification
Elbasvir and Grazoprevir: CYP3A4 Inhibitors (Strong) may increase serum concentration of Elbasvir and Grazoprevir. Management: Consider alternatives to this combination when possible. If combined, monitor for increased elbasvir/grazoprevir toxicities, including ALT elevations. Risk D: Consider Therapy Modification
Eletriptan: CYP3A4 Inhibitors (Strong) may increase serum concentration of Eletriptan. Risk X: Avoid
Elexacaftor, Tezacaftor, and Ivacaftor: CYP3A4 Inhibitors (Strong) may increase serum concentration of Elexacaftor, Tezacaftor, and Ivacaftor. Management: Administer elexacaftor/tezacaftor/ivacaftor in the morning, twice a week, 3 to 4 days apart, with no evening doses of ivacaftor alone. Specific dosing varies by age and weight. See full monograph for details. Risk D: Consider Therapy Modification
Eliglustat: CYP3A4 Inhibitors (Strong) may increase serum concentration of Eliglustat. Management: Reduce eliglustat dose to 84 mg daily in CYP2D6 EMs when used with strong CYP3A4 inhibitors. Use of strong CYP3A4 inhibitors is contraindicated in CYP2D6 IMs, PMs, or in CYP2D6 EMs who are also taking strong or moderate CYP2D6 inhibitors. Risk D: Consider Therapy Modification
Encorafenib: MiFEPRIStone may increase serum concentration of Encorafenib. Encorafenib may decrease serum concentration of MiFEPRIStone. Management: Avoid this combination when possible, especially when using mifepristone for Cushing's disease. If combined, decrease encorafenib from 450 mg to 150 mg; or from 300 mg, 225 mg, or 150 mg to 75 mg. Monitor for reduced mifepristone efficacy. Risk D: Consider Therapy Modification
Enfortumab Vedotin: Inhibitors of CYP3A4 (Strong) and P-glycoprotein may increase serum concentration of Enfortumab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be increased. Risk C: Monitor
Ensartinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ensartinib. Risk X: Avoid
Ensartinib: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Ensartinib. Risk X: Avoid
Entrectinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Entrectinib. Management: Avoid strong CYP3A4 inhibitors if possible. If needed, reduce entrectinib dose to 50 mg on alternating days if starting dose 200 mg; to 50 mg/day if starting dose 300 mg or 400 mg; to 100 mg/day if starting dose 600 mg. Risk D: Consider Therapy Modification
Eplerenone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Eplerenone. Risk X: Avoid
Erdafitinib: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Erdafitinib. Management: Avoid concomitant use of erdafitinib and moderate CYP2C9 inhibitors when possible. If combined, monitor closely for erdafitinib adverse reactions and consider dose modifications accordingly. Risk D: Consider Therapy Modification
Erdafitinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Erdafitinib. Management: Avoid concomitant use of erdafitinib and strong CYP3A4 inhibitors when possible. If combined, monitor closely for erdafitinib adverse reactions and consider dose modifications accordingly. Risk D: Consider Therapy Modification
Ergot Derivatives (Vasoconstrictive CYP3A4 Substrates): CYP3A4 Inhibitors (Strong) may increase serum concentration of Ergot Derivatives (Vasoconstrictive CYP3A4 Substrates). Risk X: Avoid
Erlotinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Erlotinib. Management: Avoid use of this combination when possible. When the combination must be used, monitor the patient closely for the development of erlotinib-associated adverse reactions, and if such severe reactions occur, reduce the erlotinib dose (in 50 mg decrements). Risk D: Consider Therapy Modification
Erythromycin (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Erythromycin (Systemic). Management: Consider alternatives to this combination when possible. If combined, monitor for increased erythromycin effects and toxicities, including QTc interval prolongation. Risk D: Consider Therapy Modification
Esketamine (Injection): CYP3A4 Inhibitors (Strong) may increase serum concentration of Esketamine (Injection). Risk C: Monitor
Estrogen Derivatives: CYP3A4 Inhibitors (Strong) may increase serum concentration of Estrogen Derivatives. Risk C: Monitor
Eszopiclone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Eszopiclone. Management: Limit the eszopiclone dose to 2 mg daily when combined with strong CYP3A4 inhibitors and monitor for increased eszopiclone effects and toxicities (eg, somnolence, drowsiness, CNS depression). Risk D: Consider Therapy Modification
Etizolam: CYP3A4 Inhibitors (Strong) may increase serum concentration of Etizolam. Risk C: Monitor
Etoposide Phosphate: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Etoposide Phosphate. Risk C: Monitor
Etoposide: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Etoposide. Risk C: Monitor
Etrasimod: MiFEPRIStone may increase serum concentration of Etrasimod. Risk X: Avoid
Everolimus: Inhibitors of CYP3A4 (Strong) and P-glycoprotein may increase serum concentration of Everolimus. Risk X: Avoid
Evogliptin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Evogliptin. Risk C: Monitor
Fedratinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Fedratinib. Management: Consider alternatives when possible. If used together, decrease fedratinib dose to 200 mg/day. After the inhibitor is stopped, increase fedratinib to 300 mg/day for the first 2 weeks and then to 400 mg/day as tolerated. Risk D: Consider Therapy Modification
Felodipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Felodipine. Management: Consider using lower felodipine doses when combined with strong CYP3A4 inhibitors. Monitor patients for increased felodipine effects and toxicities (eg, hypotension, edema) when combined. Risk D: Consider Therapy Modification
FentaNYL: MiFEPRIStone may increase serum concentration of FentaNYL. Risk X: Avoid
Fesoterodine: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Fesoterodine. Management: Limit fesoterodine doses to 4 mg daily in patients who are also receiving strong CYP3A4 inhibitors. This combination is not recommended in pediatric patients weighing 25 kg up to 35 kg. Risk D: Consider Therapy Modification
Fexinidazole: CYP3A4 Inhibitors (Strong) may decrease active metabolite exposure of Fexinidazole. Management: Avoid use of fexinidazole and strong CYP3A4 inhibitors when possible. If combined, monitor for reduced fexinidazole efficacy. Risk D: Consider Therapy Modification
Finerenone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Finerenone. Risk X: Avoid
Flibanserin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Flibanserin. Management: Use of flibanserin with strong CYP3A4 inhibitors is contraindicated. If starting flibanserin, start 2 weeks after the last dose of the CYP3A4 inhibitor. If starting a CYP3A4 inhibitor, start 2 days after the last dose of flibanserin. Risk X: Avoid
Flunitrazepam: CYP3A4 Inhibitors (Strong) may increase serum concentration of Flunitrazepam. Risk C: Monitor
Flurbiprofen (Systemic): CYP2C9 Inhibitors (Moderate) may increase serum concentration of Flurbiprofen (Systemic). Risk C: Monitor
Fluticasone (Nasal): CYP3A4 Inhibitors (Strong) may increase serum concentration of Fluticasone (Nasal). Risk X: Avoid
Fluticasone (Oral Inhalation): CYP3A4 Inhibitors (Strong) may increase serum concentration of Fluticasone (Oral Inhalation). Management: Consider alternatives to this combination if possible. Coadministration of fluticasone propionate and strong CYP3A4 inhibitors is not recommended. If combined, monitor patients for systemic corticosteroid adverse effects (eg, adrenal suppression). Risk D: Consider Therapy Modification
Fluticasone (Topical): CYP3A4 Inhibitors (Strong) may increase serum concentration of Fluticasone (Topical). Risk C: Monitor
Fluvastatin: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Fluvastatin. Management: Fluvastatin should be used at the lowest effective dose and should not exceed 20 mg twice daily when combined with moderate CYP2C9 inhibitors. Avoid coadministration of fluvastatin extended-release tablets with moderate CYP2C9 inhibitors. Risk D: Consider Therapy Modification
Fosamprenavir: May increase serum concentration of MiFEPRIStone. Management: For treatment of hyperglycemia in Cushing's syndrome, start mifepristone at 300 mg/day, may titrate to a maximum of 900 mg/day. If starting fosamprenavir and taking > 300 mg/day mifepristone, decrease the mifepristone dose by 300 mg/day. Risk D: Consider Therapy Modification
Fosaprepitant: CYP3A4 Inhibitors (Strong) may increase serum concentration of Fosaprepitant. Risk X: Avoid
Fostamatinib: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Fostamatinib. Risk C: Monitor
Fusidic Acid (Systemic): May increase serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Consider avoiding this combination if possible. If required, monitor patients closely for increased adverse effects of the CYP3A4 substrate. Risk D: Consider Therapy Modification
Futibatinib: Inhibitors of CYP3A4 (Strong) and P-glycoprotein may increase serum concentration of Futibatinib. Risk X: Avoid
Gefitinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Gefitinib. Risk C: Monitor
Gepirone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Gepirone. Risk X: Avoid
Gepotidacin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Gepotidacin. Management: Avoid coadministration of gepotidacin and strong CYP3A4 inhibitors if possible. If coadministration cannot be avoided, conduct a baseline ECG, monitor closely for altered electrolytes, and correct electrolyte abnormalities as needed. Risk D: Consider Therapy Modification
Gilteritinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Gilteritinib. Management: Consider alternatives to the use of a strong CYP3A4 inhibitor with gilteritinib. If the combination cannot be avoided, monitor more closely for evidence of gilteritinib toxicities. Risk D: Consider Therapy Modification
Glasdegib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Glasdegib. Management: Consider alternatives to this combination when possible. If the combination must be used, monitor closely for evidence of QT interval prolongation and other adverse reactions to glasdegib. Risk D: Consider Therapy Modification
Glecaprevir and Pibrentasvir: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Glecaprevir and Pibrentasvir. Risk C: Monitor
Grapefruit Juice: May increase serum concentration of MiFEPRIStone. Risk X: Avoid
GuanFACINE: CYP3A4 Inhibitors (Strong) may increase serum concentration of GuanFACINE. Management: Reduce the extended-release guanfacine dose 50% when combined with a strong CYP3A4 inhibitor. Monitor for increased guanfacine toxicities when these agents are combined. Risk D: Consider Therapy Modification
Halofantrine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Halofantrine. Management: Consider alternatives to this combination whenever possible. If combined, monitor closely for halofantrine toxicities, including QTc interval prolongation. Risk D: Consider Therapy Modification
Haloperidol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Haloperidol. Risk C: Monitor
Haloperidol: QT-prolonging Agents (Indeterminate Risk - Avoid) may increase QTc-prolonging effects of Haloperidol. Risk C: Monitor
Herbal Products with Glucose Lowering Effects: May increase hypoglycemic effects of Hypoglycemia-Associated Agents. Risk C: Monitor
Hormonal Contraceptives: MiFEPRIStone may decrease therapeutic effects of Hormonal Contraceptives. Management: Nonhormonal contraception should be used during, and for 4 weeks following, mifepristone treatment for hyperglycemia due to Cushing syndrome. If used for pregnancy termination, hormonal contraceptives can be used after pregnancy expulsion is confirmed. Risk D: Consider Therapy Modification
HYDROcodone: CYP3A4 Inhibitors (Strong) may increase serum concentration of HYDROcodone. Risk C: Monitor
Hypoglycemia-Associated Agents: May increase hypoglycemic effects of Hypoglycemia-Associated Agents. Risk C: Monitor
Ibrexafungerp: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ibrexafungerp. Management: Decrease the ibrexafungerp dose to 150 mg every 12 hours for 2 doses in patients receiving strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Ibrutinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ibrutinib. Management: Avoid concomitant use of ibrutinib and strong CYP3A4 inhibitors. If a strong CYP3A4 inhibitor must be used short-term (eg, anti-infectives for 7 days or less), interrupt ibrutinib therapy until the strong CYP3A4 inhibitor is discontinued. Risk X: Avoid
Idelalisib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Idelalisib. Management: Use alternative therapies that are not strong CYP3A4 inhibitors whenever possible. If unable to use alternative drugs, monitor patients more frequently for idelalisib toxicities. Risk D: Consider Therapy Modification
Ifosfamide: CYP3A4 Inhibitors (Strong) may increase adverse/toxic effects of Ifosfamide. CYP3A4 Inhibitors (Strong) may decrease active metabolite exposure of Ifosfamide. Risk C: Monitor
Iloperidone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Iloperidone. CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Iloperidone. Specifically, concentrations of the metabolites P88 and P95 may be increased. Management: Reduce iloperidone dose by half when administered with a strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Imatinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Imatinib. Risk C: Monitor
Imidafenacin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Imidafenacin. Risk C: Monitor
Irinotecan Products: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Irinotecan Products. Specifically, serum concentrations of SN-38 may be increased. Management: Avoid administration of strong CYP3A4 inhibitors during and within 1 week prior to irinotecan administration, unless no therapeutic alternatives to these agents exist. If combined, monitor closely for increased irinotecan toxicities. Risk D: Consider Therapy Modification
Isavuconazonium Sulfate: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Isavuconazonium Sulfate. Specifically, CYP3A4 Inhibitors (Strong) may increase isavuconazole serum concentrations. Risk X: Avoid
Isradipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Isradipine. Risk C: Monitor
Istradefylline: CYP3A4 Inhibitors (Strong) may increase serum concentration of Istradefylline. Management: Limit the maximum istradefylline dose to 20 mg daily when combined with strong CYP3A4 inhibitors and monitor for increased istradefylline effects/toxicities. Risk D: Consider Therapy Modification
Ivabradine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ivabradine. Risk X: Avoid
Ivacaftor: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ivacaftor. Management: Ivacaftor dose reductions are required; consult full drug interaction monograph content for age- and weight-specific recommendations. Risk D: Consider Therapy Modification
Ivosidenib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ivosidenib. Management: Avoid use of a strong CYP3A4 inhibitor with ivosidenib whenever possible. When combined use is required, reduce the ivosidenib dose to 250 mg once daily and monitor for increased ivosidenib toxicities, including QTc interval prolongation. Risk D: Consider Therapy Modification
Ixabepilone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ixabepilone. Management: Avoid use of ixabepilone and strong CYP3A4 inhibitors when possible. If combined, reduce the ixabepilone dose to 20 mg/m2. The previous ixabepilone dose can be resumed 1 week after discontinuation of the strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Ketamine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ketamine. Risk C: Monitor
Lacidipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lacidipine. Risk C: Monitor
Lapatinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lapatinib. Management: Avoid use of lapatinib and strong CYP3A4 inhibitors when possible. If combined, a reduced lapatinib dose of 500 mg daily should be considered. The previous lapatinib dose can be resumed 1 week after discontinuation of the strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Larotrectinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Larotrectinib. Management: Avoid use of strong CYP3A4 inhibitors with larotrectinib. If this combination cannot be avoided, reduce the larotrectinib dose by 50%. Increase to previous dose after stopping the inhibitor after a period of 3 to 5 times the inhibitor's half-life. Risk D: Consider Therapy Modification
Lefamulin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lefamulin. Management: Avoid concomitant use of lefamulin tablets and strong inhibitors of CYP3A4. Risk X: Avoid
Lemborexant: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lemborexant. Risk X: Avoid
Leniolisib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Leniolisib. Risk X: Avoid
Lercanidipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lercanidipine. Risk X: Avoid
Leuprolide and Norethindrone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Leuprolide and Norethindrone. Specifically, concentrations of norethindrone may increase. Risk C: Monitor
Levamlodipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Levamlodipine. Risk C: Monitor
Levobupivacaine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Levobupivacaine. Risk C: Monitor
Levoketoconazole: CYP3A4 Inhibitors (Strong) may increase serum concentration of Levoketoconazole. Risk X: Avoid
Levomethadone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Levomethadone. Risk C: Monitor
Levomilnacipran: CYP3A4 Inhibitors (Strong) may increase serum concentration of Levomilnacipran. Management: The dose of levomilnacipran should not exceed 80 mg once daily when used with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Lidocaine (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Lidocaine (Systemic). Risk C: Monitor
Lomitapide: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lomitapide. Risk X: Avoid
Lonafarnib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lonafarnib. Risk X: Avoid
Lorlatinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lorlatinib. Management: Avoid use of lorlatinib with strong CYP3A4 inhibitors. If the combination cannot be avoided, reduce the lorlatinib dose from 100 mg once daily to 75 mg once daily, or from 75 mg once daily to 50 mg once daily. Risk D: Consider Therapy Modification
Lornoxicam: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Lornoxicam. Risk C: Monitor
Losartan: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Losartan. CYP2C9 Inhibitors (Moderate) may decrease active metabolite exposure of Losartan. Risk C: Monitor
Lovastatin: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Lovastatin. CYP3A4 Inhibitors (Strong) may increase serum concentration of Lovastatin. Risk X: Avoid
Lumacaftor and Ivacaftor: May decrease serum concentration of MiFEPRIStone. MiFEPRIStone may increase serum concentration of Lumacaftor and Ivacaftor. Management: Avoid combined use in patients treated for Cushing's disease. When used for pregnancy termination, mifepristone efficacy may be reduced; follow-up assessment is required if combined. Lumacaftor/ivacaftor dose adjustments may be needed; see full mono. Risk D: Consider Therapy Modification
Lumateperone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lumateperone. Management: Limit the lumateperone dose to 10.5 mg once daily when used with a strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Lurasidone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lurasidone. Risk X: Avoid
Lurbinectedin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Lurbinectedin. Management: Avoid concomitant use of lurbinectedin and strong CYP3A4 inhibitors. If coadministration with a strong CYP3A4 inhibitor cannot be avoided, reduce the lurbinectedin dose by 50%. Risk D: Consider Therapy Modification
Macitentan: CYP3A4 Inhibitors (Strong) may increase serum concentration of Macitentan. Risk X: Avoid
Maitake: May increase hypoglycemic effects of Agents with Blood Glucose Lowering Effects. Risk C: Monitor
Manidipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Manidipine. Management: Consider avoiding concomitant use of manidipine and strong CYP3A4 inhibitors. If combined, monitor closely for increased manidipine effects and toxicities. Manidipine dose reductions may be required. Risk D: Consider Therapy Modification
Maraviroc: CYP3A4 Inhibitors (Strong) may increase serum concentration of Maraviroc. Management: Reduce maraviroc to 150mg twice/day in adult and pediatrics weighing 40kg or more. See full interaction monograph for dose adjustments in pediatrics weighing 10 to less than 40kg. Do not use if CrCl less than 30mL/min or in those weighing less than 10 kg. Risk D: Consider Therapy Modification
Mavacamten: CYP3A4 Inhibitors (Strong) may increase serum concentration of Mavacamten. Management: For patients on stable therapy with a strong CYP3A4 inhibitor initiate mavacamten at 2.5 mg daily. For patients initiating a strong CYP3A4 inhibitor during mavacamten therapy, dose reductions are recommended. See full mono for details. Risk D: Consider Therapy Modification
Mavorixafor: CYP3A4 Inhibitors (Strong) may increase serum concentration of Mavorixafor. Management: Decrease the mavorixafor dose to 200 mg daily if combined with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Mefloquine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Mefloquine. Risk C: Monitor
Meloxicam: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Meloxicam. Risk C: Monitor
Meperidine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Meperidine. Risk C: Monitor
Methadone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Methadone. Management: If coadministration with strong CYP3A4 inhibitors is necessary, consider methadone dose reductions until stable effects are achieved. Monitor patients closely for respiratory depression and sedation. Risk D: Consider Therapy Modification
Midazolam: CYP3A4 Inhibitors (Strong) may increase serum concentration of Midazolam. Management: Avoid use of nasal midazolam and strong CYP3A4 inhibitors whenever possible, and consider alternatives to use with other routes of midazolam (oral, IV, IM). If combined, consider lower midazolam doses and monitor for increased midazolam toxicities. Risk D: Consider Therapy Modification
Midostaurin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Midostaurin. Management: Seek alternatives to the concomitant use of midostaurin and strong CYP3A4 inhibitors if possible. If concomitant use cannot be avoided, monitor patients for increased risk of adverse reactions. Risk D: Consider Therapy Modification
Mirodenafil: CYP3A4 Inhibitors (Strong) may increase serum concentration of Mirodenafil. Management: Consider using a lower dose of mirodenafil when used with strong CYP3A4 inhibitors. Monitor for increased mirodenafil effects/toxicities with the use of this combination. Risk D: Consider Therapy Modification
Mirtazapine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Mirtazapine. Risk C: Monitor
Mirvetuximab Soravtansine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Mirvetuximab Soravtansine. Risk C: Monitor
Mitapivat: CYP3A4 Inhibitors (Strong) may increase serum concentration of Mitapivat. Risk X: Avoid
Mobocertinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Mobocertinib. CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Mobocertinib. Risk X: Avoid
Mometasone (Nasal): CYP3A4 Inhibitors (Strong) may increase serum concentration of Mometasone (Nasal). Risk C: Monitor
Mometasone (Oral Inhalation): CYP3A4 Inhibitors (Strong) may increase serum concentration of Mometasone (Oral Inhalation). Risk C: Monitor
Mometasone (Topical): CYP3A4 Inhibitors (Strong) may increase serum concentration of Mometasone (Topical). Risk C: Monitor
Monoamine Oxidase Inhibitors: May increase hypoglycemic effects of Agents with Blood Glucose Lowering Effects. Risk C: Monitor
Morphine (Systemic): P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Morphine (Systemic). Risk C: Monitor
Nadolol: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Nadolol. Risk C: Monitor
Naldemedine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Naldemedine. Risk C: Monitor
Naldemedine: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Naldemedine. Risk C: Monitor
Nalfurafine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Nalfurafine. Risk C: Monitor
Naloxegol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Naloxegol. Risk X: Avoid
Nateglinide: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Nateglinide. Risk C: Monitor
Neratinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Neratinib. Risk X: Avoid
NiCARdipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of NiCARdipine. Risk C: Monitor
NIFEdipine (Topical): CYP3A4 Inhibitors (Strong) may increase serum concentration of NIFEdipine (Topical). Risk X: Avoid
NIFEdipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of NIFEdipine. Management: Consider alternatives to this combination when possible. If combined, initiate nifedipine at the lowest dose available and monitor patients closely for increased nifedipine effects and toxicities (eg, hypotension, edema). Risk D: Consider Therapy Modification
Nilotinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Nilotinib. Management: Avoid if possible. If coadministration cannot be avoided, nilotinib dose adjustments are recommended and depend on the dosage form of nilotinib used and indication treated. See full monograph for details. Risk D: Consider Therapy Modification
Nilvadipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Nilvadipine. Risk C: Monitor
NiMODipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of NiMODipine. Risk X: Avoid
Nintedanib: Inhibitors of CYP3A4 (Strong) and P-glycoprotein may increase serum concentration of Nintedanib. Risk C: Monitor
Nirogacestat: CYP3A4 Inhibitors (Strong) may increase serum concentration of Nirogacestat. Risk X: Avoid
Nisoldipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Nisoldipine. Risk X: Avoid
Nitrendipine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Nitrendipine. Risk C: Monitor
Olaparib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Olaparib. Management: Avoid use of strong CYP3A4 inhibitors with olaparib, if possible. If such concurrent use cannot be avoided, the dose of olaparib tablets should be reduced to 100 mg twice daily and the dose of olaparib capsules should be reduced to 150 mg twice daily. Risk D: Consider Therapy Modification
Oliceridine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Oliceridine. Risk C: Monitor
Olmutinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Olmutinib. Risk C: Monitor
Omaveloxolone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Omaveloxolone. Management: Avoid this combination if possible. If coadministration is required, decrease the omaveloxolone dose to 50 mg daily and monitor closely for adverse reactions. Discontinue coadministration if adverse reactions occur. Risk D: Consider Therapy Modification
Osilodrostat: CYP3A4 Inhibitors (Strong) may increase serum concentration of Osilodrostat. Management: Reduce osilodrostat dose by 50% during coadministration with a strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Ospemifene: MiFEPRIStone may increase serum concentration of Ospemifene. Risk C: Monitor
OxyBUTYnin: CYP3A4 Inhibitors (Strong) may increase serum concentration of OxyBUTYnin. Risk C: Monitor
OxyCODONE: CYP3A4 Inhibitors (Strong) may increase adverse/toxic effects of OxyCODONE. CYP3A4 Inhibitors (Strong) may increase serum concentration of OxyCODONE. Serum concentrations of the active metabolite oxymorphone may also be increased. Risk C: Monitor
PACLitaxel (Conventional): CYP3A4 Inhibitors (Strong) may increase serum concentration of PACLitaxel (Conventional). Risk C: Monitor
PACLitaxel (Protein Bound): CYP3A4 Inhibitors (Strong) may increase serum concentration of PACLitaxel (Protein Bound). Risk C: Monitor
Pacritinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Pacritinib. Risk X: Avoid
Palbociclib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Palbociclib. Management: Avoid concurrent use of strong CYP3A4 inhibitors with palbociclib when possible. If the use of a strong CYP3A4 inhibitor cannot be avoided, decrease the palbociclib dose to 75 mg/day. Risk D: Consider Therapy Modification
Palovarotene: CYP3A4 Inhibitors (Strong) may increase serum concentration of Palovarotene. Risk X: Avoid
Panobinostat: CYP3A4 Inhibitors (Strong) may increase serum concentration of Panobinostat. Management: Reduce the panobinostat dose to 10 mg when it must be used with a strong CYP3A4 inhibitor. Monitor patient response to therapy closely for evidence of more severe adverse effects related to panobinostat therapy. Risk D: Consider Therapy Modification
Parecoxib: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Parecoxib. Specifically, serum concentrations of the active moiety valdecoxib may be increased. Management: Use the lowest effective dose of parecoxib and consider a dose reduction in patients taking moderate CYP2C9 inhibitors. Risk D: Consider Therapy Modification
Paricalcitol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Paricalcitol. Risk C: Monitor
PAZOPanib: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of PAZOPanib. Risk X: Avoid
Pegvisomant: May increase hypoglycemic effects of Agents with Blood Glucose Lowering Effects. Risk C: Monitor
Pemigatinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Pemigatinib. Management: If combined use cannot be avoided, reduce the pemigatinib dose from 13.5 mg daily to 9 mg daily, or from 9 mg daily to 4.5 mg daily. Resume prior pemigatinib dose after stopping the strong inhibitor once 3 half-lives of the inhibitor has passed. Risk D: Consider Therapy Modification
Pexidartinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Pexidartinib. Management: If combined use cannot be avoided, pexidartinib dose should be reduced as follows: reduce pexidartinib doses of 500 mg or 375 mg daily to 125 mg twice daily; reduce pexidartinib 250 mg daily to 125 mg once daily. Risk D: Consider Therapy Modification
Phenylbutazone: May decrease therapeutic effects of MiFEPRIStone. Management: Phenylbutazone should not be used for 8-12 days following mifepristone administration. Risk X: Avoid
Pimavanserin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Pimavanserin. Management: Decrease the pimavanserin dose to 10 mg daily when combined with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Pimecrolimus: CYP3A4 Inhibitors (Strong) may decrease metabolism of Pimecrolimus. Risk C: Monitor
Pimozide: CYP3A4 Inhibitors (Strong) may increase serum concentration of Pimozide. Risk X: Avoid
Piperaquine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Piperaquine. Risk C: Monitor
Pirtobrutinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Pirtobrutinib. Management: Avoid concomitant use when possible. If combined, reduce the pirtobrutinib dose by 50 mg. If current dose is 50 mg, interrupt pirtobrutinib treatment during strong CYP3A4 inhibitor use. Risk D: Consider Therapy Modification
Polatuzumab Vedotin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Polatuzumab Vedotin. Exposure to unconjugated MMAE, the cytotoxic small molecule component of polatuzumab vedotin, may be increased. Risk C: Monitor
PONATinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of PONATinib. Management: Avoid concomitant use if possible. If combined, reduce ponatinib dose as follows: If taking 45 mg, reduce to 30 mg; if taking 30 mg, reduce to 15 mg; if taking 15 mg, reduce to 10 mg. If taking 10 mg, avoid concomitant use with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Pralsetinib: Inhibitors of CYP3A4 (Strong) and P-glycoprotein may increase serum concentration of Pralsetinib. Management: Avoid concomitant use if possible. If combined, reduce the pralsetinib dose. If taking 400 mg or 300 mg once daily, reduce to 200 mg once daily. If taking 200 mg once daily, reduce to 100 mg once daily. Risk D: Consider Therapy Modification
Prazepam: CYP3A4 Inhibitors (Strong) may increase serum concentration of Prazepam. Risk C: Monitor
Praziquantel: CYP3A4 Inhibitors (Strong) may increase serum concentration of Praziquantel. Risk C: Monitor
Propafenone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Propafenone. Risk C: Monitor
Prothionamide: May increase hypoglycemic effects of Agents with Blood Glucose Lowering Effects. Risk C: Monitor
QT-prolonging Agents (Highest Risk): QT-prolonging Agents (Indeterminate Risk - Avoid) may increase QTc-prolonging effects of QT-prolonging Agents (Highest Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QUEtiapine: CYP3A4 Inhibitors (Strong) may increase serum concentration of QUEtiapine. Management: In quetiapine treated patients, reduce quetiapine to one-sixth of original dose after starting a strong CYP3A4 inhibitor. In those on strong CYP3A4 inhibitors, start quetiapine at lowest dose and up-titrate as needed. Risk D: Consider Therapy Modification
Quinidine (Non-Therapeutic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Quinidine (Non-Therapeutic). Risk C: Monitor
QuiNIDine: MiFEPRIStone may increase QTc-prolonging effects of QuiNIDine. MiFEPRIStone may increase serum concentration of QuiNIDine. Risk X: Avoid
QuiNINE: CYP3A4 Inhibitors (Strong) may increase serum concentration of QuiNINE. Risk C: Monitor
Quinolones: May increase hypoglycemic effects of Agents with Blood Glucose Lowering Effects. Quinolones may decrease therapeutic effects of Agents with Blood Glucose Lowering Effects. Specifically, if an agent is being used to treat diabetes, loss of blood sugar control may occur with quinolone use. Risk C: Monitor
Quizartinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Quizartinib. Management: If combination is necessary, reduce quizartinib dose as follows: from 53 mg daily to 26.5 mg daily; from 35.4 mg daily to 17.7 mg daily; from 26.5 mg daily to 17.7 mg daily. If taking 17.7 mg daily avoid quizartinib while on the strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Radotinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Radotinib. Risk X: Avoid
Ramelteon: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Ramelteon. Risk C: Monitor
Ranolazine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ranolazine. Risk X: Avoid
Reboxetine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Reboxetine. Risk C: Monitor
Red Yeast Rice: CYP3A4 Inhibitors (Strong) may increase serum concentration of Red Yeast Rice. Specifically, concentrations of lovastatin and related compounds found in Red Yeast Rice may be increased. Risk X: Avoid
Regorafenib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Regorafenib. CYP3A4 Inhibitors (Strong) may decrease active metabolite exposure of Regorafenib. Risk X: Avoid
Relugolix, Estradiol, and Norethindrone: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Relugolix, Estradiol, and Norethindrone. Management: Avoid use of relugolix/estradiol/norethindrone with P-glycoprotein (P-gp) inhibitors. If concomitant use is unavoidable, relugolix/estradiol/norethindrone should be administered at least 6 hours before the P-gp inhibitor. Risk D: Consider Therapy Modification
Relugolix: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Relugolix. Management: Avoid coadministration of relugolix with oral P-gp inhibitors whenever possible. If combined, take relugolix at least 6 hours prior to the P-gp inhibitor and monitor patients more frequently for adverse reactions. Risk D: Consider Therapy Modification
Repaglinide: CYP3A4 Inhibitors (Strong) may increase serum concentration of Repaglinide. Risk C: Monitor
Repotrectinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Repotrectinib. Risk X: Avoid
Retapamulin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Retapamulin. Management: The use of retapamulin with strong CYP3A4 inhibitors is not recommended in patients less than 2 years old. No action is required in other populations. Risk C: Monitor
Revumenib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Revumenib. Management: If combined use is required, decrease revumenib dose for patients weighing 40 kg or more to 160 mg orally twice/day; for patients weighing less than 40 kg to 95 mg/m2 twice daily. Risk D: Consider Therapy Modification
Ribociclib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ribociclib. Management: Avoid use of ribociclib with strong CYP3A4 inhibitors when possible; if combined use cannot be avoided, reduce ribociclib dose to 400 mg once daily in advanced or metastatic breast cancer; reduce ribociclib dose to 200 mg daily in early breast cancer. Risk D: Consider Therapy Modification
RifAXIMin: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of RifAXIMin. Risk C: Monitor
Rilpivirine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Rilpivirine. Risk C: Monitor
Rimegepant: CYP3A4 Inhibitors (Strong) may increase serum concentration of Rimegepant. Risk X: Avoid
Riociguat: Inhibitors of CYP3A4 (Strong) and P-glycoprotein may increase serum concentration of Riociguat. Management: Consider a riociguat starting dose of 0.5 mg 3 times a day when initiating riociguat in patients receiving strong CYP3A4 and P-gp inhibitors. Monitor for hypotension when these agents are combined and reduce the riociguat dose as needed. Risk D: Consider Therapy Modification
Ripretinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ripretinib. CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Ripretinib. Risk C: Monitor
RisperiDONE: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of RisperiDONE. Risk C: Monitor
Rivaroxaban: Inhibitors of CYP3A4 (Strong) and P-glycoprotein may increase serum concentration of Rivaroxaban. Risk X: Avoid
Roflumilast-Containing Products: CYP3A4 Inhibitors (Strong) may increase serum concentration of Roflumilast-Containing Products. Risk C: Monitor
RomiDEPsin: CYP3A4 Inhibitors (Strong) may increase serum concentration of RomiDEPsin. Risk C: Monitor
RomiDEPsin: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of RomiDEPsin. Risk C: Monitor
Rupatadine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Rupatadine. Risk X: Avoid
Ruxolitinib (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Ruxolitinib (Systemic). Management: This combination should be avoided under some circumstances; dose adjustments may be required in some circumstances and depend on the indication for ruxolitinib. See monograph for details. Risk D: Consider Therapy Modification
Ruxolitinib (Topical): CYP3A4 Inhibitors (Strong) may increase serum concentration of Ruxolitinib (Topical). Risk X: Avoid
Salicylates: May increase hypoglycemic effects of Agents with Blood Glucose Lowering Effects. Risk C: Monitor
Salmeterol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Salmeterol. Risk X: Avoid
SAXagliptin: CYP3A4 Inhibitors (Strong) may increase serum concentration of SAXagliptin. Management: Limit the saxagliptin dose to 2.5 mg daily when combined with strong CYP3A4 inhibitors. When using the saxagliptin combination products saxagliptin/dapagliflozin or saxagliptin/dapagliflozin/metformin, avoid use with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Seladelpar: Inhibitors of CYP3A4 and CYP2C9 may increase serum concentration of Seladelpar. Risk C: Monitor
Selective Serotonin Reuptake Inhibitor: May increase hypoglycemic effects of Agents with Blood Glucose Lowering Effects. Risk C: Monitor
Selpercatinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Selpercatinib. Management: Avoid combination if possible. If use is necessary, reduce selpercatinib dose as follows: from 120 mg twice/day to 40 mg twice/day, or from 160 mg twice/day to 80 mg twice/day. Risk D: Consider Therapy Modification
Selumetinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Selumetinib. Management: Avoid concomitant use when possible. If combined, selumetinib dose reductions are recommended and vary based on body surface area and selumetinib dose. For details, see the full drug interaction monograph or selumetinib prescribing information. Risk D: Consider Therapy Modification
Sertindole: CYP3A4 Inhibitors (Strong) may increase serum concentration of Sertindole. Risk X: Avoid
Sildenafil: CYP3A4 Inhibitors (Strong) may increase serum concentration of Sildenafil. Management: Use of sildenafil for pulmonary arterial hypertension (PAH) should be avoided with strong CYP3A4 inhibitors. When used for erectile dysfunction, consider using a lower starting dose of 25 mg and monitor patients for sildenafil toxicities. Risk D: Consider Therapy Modification
Silodosin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Silodosin. Risk X: Avoid
Simeprevir: CYP3A4 Inhibitors (Strong) may increase serum concentration of Simeprevir. Risk X: Avoid
Simvastatin: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Simvastatin. CYP3A4 Inhibitors (Strong) may increase serum concentration of Simvastatin. Risk X: Avoid
Siponimod: MiFEPRIStone may increase serum concentration of Siponimod. Risk X: Avoid
Sirolimus (Conventional): CYP3A4 Inhibitors (Strong) may increase serum concentration of Sirolimus (Conventional). Management: Avoid concurrent use of sirolimus with strong CYP3A4 inhibitors when possible and alternative agents with lesser interaction potential with sirolimus should be considered. Concomitant use of sirolimus and voriconazole or posaconazole is contraindicated. Risk D: Consider Therapy Modification
Sirolimus (Protein Bound): CYP3A4 Inhibitors (Strong) may increase serum concentration of Sirolimus (Protein Bound). Risk X: Avoid
Sirolimus (Topical): CYP3A4 Inhibitors (Strong) may increase serum concentration of Sirolimus (Topical). Risk C: Monitor
Solifenacin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Solifenacin. Management: Limit adult solifenacin doses to 5 mg daily and limit doses in pediatric patients to the recommended weight-based starting dose (and do not increase the dose) when combined with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Solriamfetol: May increase hypertensive effects of Hypertension-Associated Agents. Risk C: Monitor
Sonidegib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Sonidegib. Risk X: Avoid
Sparsentan: CYP3A4 Inhibitors (Strong) may increase serum concentration of Sparsentan. Risk X: Avoid
SUFentanil: CYP3A4 Inhibitors (Strong) may increase serum concentration of SUFentanil. Management: If a strong CYP3A4 inhibitor is initiated in a patient on sufentanil, consider a sufentanil dose reduction and monitor for increased sufentanil effects and toxicities (eg, respiratory depression). Risk D: Consider Therapy Modification
Sulfonylureas: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Sulfonylureas. Risk C: Monitor
SUNItinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of SUNItinib. Management: Avoid when possible. If combined, decrease sunitinib dose to a minimum of 37.5 mg daily when treating GIST or RCC. Decrease sunitinib dose to a minimum of 25 mg daily when treating PNET. Monitor patients for both reduced efficacy and increased toxicities. Risk D: Consider Therapy Modification
Suvorexant: CYP3A4 Inhibitors (Strong) may increase serum concentration of Suvorexant. Risk X: Avoid
Suzetrigine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Suzetrigine. Risk X: Avoid
Tacrolimus (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Tacrolimus (Systemic). Management: Reduce tacrolimus dose to one-third of the original dose if starting posaconazole or voriconazole. Coadministration with nelfinavir is not generally recommended. Tacrolimus dose reductions or prolongation of dosing interval will likely be required. Risk D: Consider Therapy Modification
Tacrolimus (Topical): CYP3A4 Inhibitors (Strong) may increase serum concentration of Tacrolimus (Topical). Risk C: Monitor
Tadalafil: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tadalafil. Management: Avoid this combination in patients taking tadalafil for pulmonary arterial hypertension. In patients taking tadalafil for ED or BPH, max tadalafil dose is 2.5 mg if taking daily or 10 mg no more frequently than every 72 hours if used as needed. Risk D: Consider Therapy Modification
Talazoparib: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Talazoparib. Risk C: Monitor
Tamsulosin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tamsulosin. Risk X: Avoid
Tasimelteon: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tasimelteon. Risk C: Monitor
Tazemetostat: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tazemetostat. Risk X: Avoid
Temsirolimus: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Temsirolimus. Specifically, concentrations of sirolimus may be increased. Management: Avoid concomitant use of temsirolimus and strong CYP3A4 inhibitors. If coadministration is unavoidable, decrease temsirolimus dose to 12.5 mg per week. Resume previous temsirolimus dose 1 week after discontinuation of the strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Teniposide: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Teniposide. Risk C: Monitor
Tenofovir Disoproxil Fumarate: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Tenofovir Disoproxil Fumarate. Risk C: Monitor
Tenoxicam: May decrease therapeutic effects of MiFEPRIStone. Risk C: Monitor
Tetrahydrocannabinol and Cannabidiol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tetrahydrocannabinol and Cannabidiol. Risk C: Monitor
Tetrahydrocannabinol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tetrahydrocannabinol. Risk C: Monitor
Tezacaftor and Ivacaftor: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tezacaftor and Ivacaftor. Management: If combined with strong CYP3A4 inhibitors, tezacaftor/ivacaftor should be administered in the morning, twice a week, approximately 3 to 4 days apart. Tezacaftor/ivacaftor dose depends on age and weight; see full Lexi-Interact monograph for details. Risk D: Consider Therapy Modification
Thiotepa: CYP3A4 Inhibitors (Strong) may decrease active metabolite exposure of Thiotepa. CYP3A4 Inhibitors (Strong) may increase serum concentration of Thiotepa. Management: Avoid coadministration of thiotepa and strong CYP3A4 inhibitors. If concomitant use cannot be avoided, monitor for thiotepa adverse effects and decreased efficacy. Risk D: Consider Therapy Modification
Ticagrelor: CYP3A4 Inhibitors (Strong) may decrease active metabolite exposure of Ticagrelor. CYP3A4 Inhibitors (Strong) may increase serum concentration of Ticagrelor. Risk X: Avoid
Tilidine: CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Tilidine. CYP3A4 Inhibitors (Strong) may increase serum concentration of Tilidine. Risk C: Monitor
Tisotumab Vedotin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tisotumab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be increased. Risk C: Monitor
Tofacitinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tofacitinib. Management: Tofacitinib dose reductions are recommended when combined with strong CYP3A4 inhibitors. Recommended dose adjustments vary by tofacitinib formulation and therapeutic indication. See full Lexi Interact monograph for details. Risk D: Consider Therapy Modification
Tolterodine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tolterodine. Management: The maximum recommended dose of tolterodine is 2 mg per day (1 mg twice daily for immediate-release tablets or 2 mg daily for extended-release capsules) when used together with a strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Tolvaptan: CYP3A4 Inhibitors (Strong) may increase serum concentration of Tolvaptan. Risk X: Avoid
Topotecan: P-glycoprotein/ABCB1 Inhibitors may increase serum concentration of Topotecan. Risk X: Avoid
Toremifene: CYP3A4 Inhibitors (Strong) may increase serum concentration of Toremifene. Management: Use of toremifene with strong CYP3A4 inhibitors should be avoided if possible. If coadministration is necessary, monitor for increased toremifene toxicities, including QTc interval prolongation. Risk D: Consider Therapy Modification
Torsemide: CYP2C9 Inhibitors (Moderate) may increase serum concentration of Torsemide. Risk C: Monitor
Trabectedin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Trabectedin. Risk X: Avoid
TraMADol: CYP3A4 Inhibitors (Strong) may increase serum concentration of TraMADol. CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of TraMADol. Risk C: Monitor
TraZODone: CYP3A4 Inhibitors (Strong) may increase serum concentration of TraZODone. Management: Consider the use of a lower trazodone dose and monitor for increased trazodone effects (eg, sedation, QTc prolongation) if combined with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Tretinoin (Systemic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Tretinoin (Systemic). Management: Avoid use of tretinoin and strong CYP3A4 inhibitors when possible. If combined, monitor for increased tretinoin concentrations and toxicities (eg, pseudotumor cerebri, hypercalcemia). Risk D: Consider Therapy Modification
Triamcinolone (Nasal): CYP3A4 Inhibitors (Strong) may increase serum concentration of Triamcinolone (Nasal). Risk C: Monitor
Triamcinolone (Ophthalmic): CYP3A4 Inhibitors (Strong) may increase serum concentration of Triamcinolone (Ophthalmic). Risk C: Monitor
Triamcinolone (Topical): CYP3A4 Inhibitors (Strong) may increase serum concentration of Triamcinolone (Topical). Risk C: Monitor
Triazolam: CYP3A4 Inhibitors (Strong) may increase serum concentration of Triazolam. Risk X: Avoid
Ubrogepant: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ubrogepant. Risk X: Avoid
Udenafil: CYP3A4 Inhibitors (Strong) may increase serum concentration of Udenafil. Risk X: Avoid
Ulipristal: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ulipristal. Risk C: Monitor
Upadacitinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Upadacitinib. Management: Upadacitinib dose adjustments are often needed when combined with strong CYP3A4 inhibitors. Specific adjustments vary based on upadacitinib indication. See full interact monograph for details. Risk D: Consider Therapy Modification
Valbenazine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Valbenazine. CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Valbenazine. Management: Reduce the valbenazine dose to 40 mg daily when combined with strong CYP3A4 inhibitors. Risk D: Consider Therapy Modification
Vanzacaftor, Tezacaftor, and Deutivacaftor: CYP3A4 Inhibitors (Strong) may increase serum concentration of Vanzacaftor, Tezacaftor, and Deutivacaftor. Management: Age- and weight-specific dose reductions of vanzacaftor, tezacaftor, and deutivacaftor are recommended. Please see full Interact monograph or labeling for details. Risk D: Consider Therapy Modification
Vardenafil: CYP3A4 Inhibitors (Strong) may increase serum concentration of Vardenafil. Management: Limit Levitra (vardenafil) dose to a single 2.5 mg dose within a 24-hour period if combined with strong CYP3A4 inhibitors. Avoid concomitant use of Staxyn (vardenafil) and strong CYP3A4 inhibitors. Combined use is contraindicated outside of the US. Risk D: Consider Therapy Modification
Vemurafenib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Vemurafenib. Management: Avoid concurrent use of vemurafenib with strong CYP3A4 inhibitors when possible. If concomitant use is unavoidable, consider a vemurafenib dose reduction if clinically indicated. Risk D: Consider Therapy Modification
Venetoclax: CYP3A4 Inhibitors (Strong) may increase serum concentration of Venetoclax. Management: Coadministration is contraindicated during venetoclax initiation and ramp-up in CLL/SLL patients. Reduced venetoclax doses are required during ramp-up for patients with AML, and all maintenance therapy. See full Lexi Interact monograph for details. Risk D: Consider Therapy Modification
Verapamil: CYP3A4 Inhibitors (Strong) may increase serum concentration of Verapamil. Risk C: Monitor
Vilanterol: CYP3A4 Inhibitors (Strong) may increase serum concentration of Vilanterol. Risk C: Monitor
Vilazodone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Vilazodone. Management: Limit the maximum vilazodone dose to 20 mg daily in patients receiving strong CYP3A4 inhibitors. The original vilazodone dose can be resumed following discontinuation of the strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
VinBLAStine: CYP3A4 Inhibitors (Strong) may increase serum concentration of VinBLAStine. Risk C: Monitor
VinCRIStine: CYP3A4 Inhibitors (Strong) may increase serum concentration of VinCRIStine. Risk X: Avoid
Vindesine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Vindesine. Risk C: Monitor
Vinflunine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Vinflunine. CYP3A4 Inhibitors (Strong) may increase active metabolite exposure of Vinflunine. Risk X: Avoid
Vinorelbine: CYP3A4 Inhibitors (Strong) may increase serum concentration of Vinorelbine. Risk C: Monitor
Vitamin K Antagonists: MiFEPRIStone may increase adverse/toxic effects of Vitamin K Antagonists. Specifically, the risk of bleeding may be increased. MiFEPRIStone may increase serum concentration of Vitamin K Antagonists. Risk X: Avoid
Voclosporin: CYP3A4 Inhibitors (Strong) may increase serum concentration of Voclosporin. Risk X: Avoid
Vorapaxar: CYP3A4 Inhibitors (Strong) may increase serum concentration of Vorapaxar. Risk X: Avoid
Zanubrutinib: CYP3A4 Inhibitors (Strong) may increase serum concentration of Zanubrutinib. Management: Decrease the zanubrutinib dose to 80 mg once daily during coadministration with a strong CYP3A4 inhibitor. Further dose adjustments may be required for zanubrutinib toxicities, refer to prescribing information for details. Risk D: Consider Therapy Modification
Ziprasidone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Ziprasidone. Risk C: Monitor
Zolpidem: CYP3A4 Inhibitors (Strong) may increase serum concentration of Zolpidem. Risk C: Monitor
Zopiclone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Zopiclone. Management: If coadministered with strong CYP3A4 inhibitors, initiate zopiclone at 3.75 mg in adults, with a maximum dose of 5 mg. Monitor for zopiclone toxicity (eg, drowsiness, confusion, lethargy, ataxia, respiratory depression). Risk D: Consider Therapy Modification
Zuranolone: CYP3A4 Inhibitors (Strong) may increase serum concentration of Zuranolone. Management: Reduce the zuranolone dose to 30 mg once daily when used concomitantly with a strong CYP3A4 inhibitor. Risk D: Consider Therapy Modification
Grapefruit juice may inhibit mifepristone metabolism, leading to increased levels. Management: Do not take with grapefruit juice.
When used to control hyperglycemia in patients with Cushing syndrome (Korlym), pregnancy must be excluded before the initiation of treatment with mifepristone. Patients who may become pregnant should use effective contraception during therapy and for 1 month after the last mifepristone dose. Mifepristone interferes with the effectiveness of hormonal contraceptives, therefore a nonhormonal, medically acceptable method of contraception is required unless the patient has had a surgical sterilization, in which case, no additional contraception is needed. Pregnancy must also be excluded if treatment is interrupted for more than 14 days in patients who could become pregnant.
Mifeprex is used for pregnancy termination (medication abortion). In sexually active patients, pregnancy can occur prior to the first menstrual period following treatment. Appropriate contraception can be started as soon as termination of pregnancy is confirmed or before sexual intercourse is resumed. Pregnancy termination via medication abortion does not adversely affect future fertility (ACOG 2020).
Korlym is contraindicated in pregnant patients to control hyperglycemia with Cushing syndrome. Mifepristone is a potent antagonist of progesterone and cortisol; the antiprogestational effects will result in the termination of pregnancy.
Mifeprex is used to terminate intrauterine pregnancy through 70 days gestation. If treatment fails, there is a risk of fetal malformation. Pregnancy termination via medication abortion does not adversely affect future pregnancy outcomes (ACOG 2020). If present, remove intrauterine device (IUD) before treatment begins. Consider the possibility of ectopic pregnancy in patients who become pregnant with an IUD in place. For consultation, health care providers may call Danco Laboratories (877-432-7596) 24 hours a day, 7 days a week to speak with an expert.
Mifepristone in combination with misoprostol is also used off-label for the treatment of early pregnancy loss (miscarriage, <13 weeks' gestation), defined as a nonviable, intrauterine pregnancy with either an empty gestational sac or a gestational sac containing an embryo or fetus without fetal heart activity. Use may be considered in patients who do not want to undergo surgical evacuation and who do not show signs of an infection, hemorrhage, severe anemia, or bleeding disorders (ACOG 2018).
Mifepristone is present in breast milk.
Mifepristone milk concentrations were evaluated in lactating women receiving a single dose for the termination of pregnancy. In women receiving mifepristone 200 mg (n = 2), milk concentrations were below the limit of detection (<0.013 micromole/L) in samples collected over the following 5 days. The highest milk concentration following a single 600 mg dose (n = 10) was 0.913 micromole/L on day 1 and concentrations decreased to 0.062 micromole/L by day 5. Using the highest reported milk concentration, the authors calculated the relative infant dose to be ≤1.5% of the weight adjusted maternal dose in a fully breast-fed infant (Sääv 2010).
Regardless of indication, the manufacturer recommends that the decision to breastfeed during therapy should consider the risk of infant exposure, the benefits of breastfeeding to the infant, and benefits of treatment to the mother.
Korlym: To minimize exposure to a breastfed infant, the manufacturer recommends pumping and discarding milk during treatment and for 18 to 21 days (5 to 6 half-lives) after the last dose.
Mifeprex: When used for the termination of pregnancy, also refer to the Misoprostol monograph for additional information.
Treatment of hyperglycemia in patients with Cushing syndrome: Signs and symptoms of adrenal insufficiency (serum cortisol concentrations will not be accurate); thyroid function; serum potassium (1 to 2 weeks after initiating dose or dose increase, then periodically thereafter); serum glucose and psychiatric symptoms (may show response to therapy within 6 weeks); cushingoid appearance (acne, hirsutism, striae, weight may take >2 months of therapy to show improvement); verify pregnancy status prior to use; evaluate unexplained vaginal bleeding that occurs during therapy.
Pregnancy termination:
Prior to treatment, confirm pregnancy, estimate gestational age, and determine Rh status; assess hemoglobin and hematocrit if anemia is suspected (ACOG 2020). Pregnancy is dated from day 1 of last menstrual period (presuming a 28-day cycle, ovulation occurring midcycle). Pregnancy duration can be determined using menstrual history and clinical examination. Use ultrasound if duration of pregnancy is uncertain or if ectopic pregnancy is suspected.
Following procedure: Clinical exam, human Chorionic Gonadotropin (hCG) testing, evaluation of symptoms, and/or ultrasound to confirm complete termination of pregnancy (ACOG 2020). Additional evaluations may be needed in patients reporting fever with or without abdominal pain, sustained fever, severe abdominal pain, prolonged heavy bleeding, syncope, or general malaise (including weakness, nausea, vomiting, or diarrhea) for more than 24 hours after taking misoprostol. In cases of an uncomplicated medication abortion, a telephone evaluation 1 week after treatment and an in-home pregnancy test 4 weeks after treatment can be done to avoid in-person visits when allowed by local laws. Perform in-person clinical exams when medically indicated or preferred by the patient (ACOG 2020).
Early pregnancy loss: Evaluate Rh status; ultrasound or serial serum hCG (if ultrasound not available) 1 to 2 weeks after dosing; patient reported symptoms (ACOG 2018).
Mifepristone is a synthetic steroid. At low doses, it competitively binds to the intracellular progesterone receptor, blocking the effects of progesterone. When used for pregnancy termination, this leads to contraction-inducing activity in the myometrium. In the absence of progesterone, mifepristone acts as a partial progesterone agonist. At high doses used for the treatment of hyperglycemia in patients with Cushing’s syndrome, mifepristone blocks the effect of cortisol at the glucocorticoid receptor (antagonizes the effects of cortisol on glucose metabolism) while at the same time increasing circulating cortisol concentrations.
Absorption: Oral: Rapid
Protein binding: 98% to albumin and α1-acid glycoprotein
Metabolism: Hepatic via CYP3A4 to three metabolites (active)
Bioavailability: Oral: 69%
Half-life elimination: Single dose: Terminal: 18 hours following a slower phase where 50% eliminated between 12-72 hours; Multiple doses (600 mg/day): 85 hours
Time to peak: Oral: 90 minutes; Range: Single dose: 1-2 hours, Multiple doses: 1-4 hours
Excretion: Feces (83%); urine (9%)
